Interaction of an interfacial crack with linear small defects under out-of-plane shear loading

The interaction of an interfacial crack with small impurities is analysed on the basis of an asymptotic formula derived by the authors. The interaction between the main crack and the defects (e.g. small cracks or inclusions) is described asymptotically by analysing the dipole fields and the corresponding dipole matrices of the defects in question. The method is generic, and it serves interfacial cracks with general distributed loading on the crack faces, taking into account possible asymmetry in the boundary conditions, and in a particular configuration for a crack in a homogeneous medium results agree with those obtained earlier by Gong [1]. Shielding and amplification effects of the defects on the propagation of the main crack along the interface are investigated. Numerical computations based on the explicit analytical formulae show potential applications in the design of composite and fibre reinforced materials.

Research highlightsWe model Mode III interfacial crack interacting with small defects. Analytical formulae are based on the dipole matrix and weight-function approach. Small defect influences the SIF leading to shielding and amplification effects. Results fully account for arbitrary loading on the crack faces.